I have no shortcuts to offer but two hours is a little more than seven minutes a valve and that ain't to bad. Did you have the heads off or replaced them while still bolted on ? I have tried the rope in the bore trick and while it does work, it was such a pain that I just pulled the heads as I figured I was gonna screw up and have to anyway. Got a spare set of heads!? Good luck and let us know what you end up doing.

They make a tool where you take out your sparkplugs and you screw in a hose connected to an air compressor. Doing so will hold the valves in place when the springs are off. I've done this when replacing the seals on my buddys 87' 350. Worked great. Take note that when you put the air pressure in the cylinder the engine might turn a little bit at first as the pressure pushes the piston down so be carfull of belts and pulleys.

If you can't find the tool I had a boss in an auto shop that made one out of an old spark plug that he broke the ceramic out of and then brazed a hose fitting into to make one. This was back in 79 and I was amazed at how well it worked.